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Materials Properties Model of Aging Concrete RECLAMManagAingTWateIr iOn theNWest Report DSO-05-05 Materials Properties Model of Aging Concrete Dam Safety Technology Development Program U.S. Department of the Interior Bureau of Reclamation Technical Service Center Denver, Colorado December 2005 Form Approved REPORT DOCUMENTATION PAGE OMB No. 0704-0188 The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 2. REPORT TYPE 3. DATES COVERED (From - To) 12-2005 Technical 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Materials Properties Model of Aging Concrete 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Timothy P. Dolen, P.E. 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT Bureau of Reclamation NUMBER Technical Service Center DSO-05-05 Water Resources Research Laboratory Denver, Colorado 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) Bureau of Reclamation Denver, Colorado 11. SPONSOR/MONITOR’S REPORT NUMBER(S) DSO-05-05 12. DISTRIBUTION/AVAILABILITY STATEMENT National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161 13. SUPPLEMENTARY NOTES 14. ABSTRACT A database model of aging concrete was developed to identify the changes in materials properties over time for Bureau of Reclamation (Reclamation) mass concrete dams. Materials properties data on mass concrete were input to the Reclamation Aging Concrete Information System (ACIS). The data were analyzed for trends in the deterioration of concretes subject to aging, including alkali aggregate reaction (AAR) and general aging of early twentieth century concrete with high water-to- cement ratios. The aging concretes were compared to dams of similar age, but not suffering from aging processes. The aging concretes were also compared to known good quality concretes that were manufactured after about 1948 to specifically resist deterioration from AAR, freezing and thawing (FT), and sulfate attack. Trends were established for comparing the compressive strength, splitting and direct tensile strength, and elastic properties of aging and non-aging dams. The strength and elastic properties of aging mass concrete differed significantly from those of comparable non-aging concretes. Both spatial variations within a structure and long-term changes in strength and elastic properties were identified. The ACIS database can be used to track the long-term materials properties behavior of dams through comprehensive concrete coring and testing programs. Laboratory core test data are included for dams ranging from about 10 to more then 83 years old. These data provide the necessary supporting documentation for the Dam Safety Office Comprehensive Facilities Review evaluation process and for dams in need of corrective action. 15. SUBJECT TERMS Concrete deterioration timeline; dam safety; materials properties model; aging concrete database; mass concrete; alkali aggregate reaction; alkali silica reaction; freezing and thawing; concrete core tests; compressive strength; splitting tensile strength; direct tensile strength; modulus of elasticity; Poisson’s ratio 16. SECURITY CLASSIFICATION OF: 17. LIMITATION 18. NUMBER 19a. NAME OF RESPONSIBLE PERSON OF ABSTRACT OF PAGES SAR 50 a. REPORT b. ABSTRACT a. THIS PAGE 19b. TELEPHONE NUMBER (Include area code) U U U Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18 BUREAU OF RECLAMATION Technical Service Center, Denver, Colorado Materials Engineering and Research Laboratory, 86-681 80 Report DSO-05-05 Materials Properties Model of Aging Concrete Dam Safety Technology Development Program Denver, Colorado Pre~ared:~imwv P. Dolen. P.E. ~esearchCivil Eniineer, senior Technical S~ecialist MaterialsZJL Engineein and /di Reslarch ~aboraiory, 86-681 90 Data Input ~heckewimoth~P. Dolen, P.E. Research Civil Engineer, Senior Technical Specialist Materials Engineering and Research Laboratory, 86-68190 \2/(,fdl Technical Approval: William ~.'~epler,P.E. Manager, ate rials Engineering . and Research Laboratory, 86-68180 3/'A7 Peer Review: William F. Kepler, P.E. Date Manager, Materials Engineering and Research Laboratory, 86-68180 REVISIONS - Date Description u u 5 3 ?! Ya, .- 3 ,-.a, Ei Ei wo E6 a> a 5 ,-<gg 2; Mission Statements The mission of the Department of the Interior is to protect and provide access to our Nation’s natural and cultural heritage and honor our trust responsibilities to Indian Tribes and our commitments to island communities. The mission of the Bureau of Reclamation is to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public. Acknowledgments The author would like to acknowledge the Science and Technology Program for providing the initial funding that led to the development of the aging concrete information system (ACIS) database and for documentation of the state of the art in Bureau of Reclamation mass concrete technology. These benefits have been invaluable in understanding those structures most in need of attention. The Dam Safety Office provided funding for the Materials Model of Aging Concrete and this final report. Dam Safety project funding was used to input much of the data on alkali-silica-affected dams and other aging dams currently under investigation. The Manuals and Standards funding allowed documentation of baseline materials properties of many of the Bureau of Reclamation’s historic dams. Several personnel from the Materials Engineering and Research Laboratory performed time-consuming, tedious data input including Erin Gleason, Veronica Madera, Jalena Maestas, and Kattie Bartojay. Lelon Lewis edited this report. Kurt von Fay began the initial work using Access programming software to develop the concept for the aggregate materials database, which provides an important resource to be coupled to the concrete properties database. He is also instrumental in the product development of concrete deterioration service life prediction software. Dr. David Harris and Dr. William Kepler provided the leadership for accomplishment of this program. Carol Hovenden performed the Access database programming development and is largely responsible for the database organizational structure, operations and maintenance, and development of data reporting modules of the ACIS database. Lastly, the author would like to thank the hundreds of Bureau of Reclamation field construction laboratory personnel, drill crews, and the Denver laboratory materials engineering technicians and engineers who have performed the backbreaking work to the perform concrete construction tests, and obtained and tested the hundreds of cores reported in the ACIS database. iii Contents Page Acknowledgments..................................................................................................iii Research Program Summary................................................................................... 1 Conclusions and Recommendations ....................................................................... 3 Aging Concrete Dams............................................................................................. 4 Reclamation’s Aging Concrete Infrastructure .................................................. 4 A Timeline for Reclamation Aging Concrete................................................... 4 Concrete Deterioration and Dam Safety........................................................... 6 Concrete Materials Properties Investigations and the Aging Concrete Information System........................................................................................... 6 ACIS and Materials Model for Aging Concrete..................................................... 9 Concrete Deterioration Model for Dams .......................................................... 9 Strength and Elastic Properties of Aging and/or ASR-Affected Dams Compared to Unaffected Dams....................................................................... 10 Averaging and Sorting of ACIS Test Data ............................................... 10 Compressive Strength and Elastic Properties Development of Aging Dams ......................................................................................................... 10 Compressive Strength and Elastic Properties Development of ASR- Affected Dams .......................................................................................... 12 Tensile Strength Properties of Aging/ASR and Non-ASR-Affected Dams ......................................................................................................... 15 Applications of Materials Properties
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